When specifying where the various Keilim (Holy Vessels) need to be positioned in the Mishkan, the Torah states that the Shulchan (Showbread Table) must be in the Kodesh (the chamber immediately connected to the Kodesh Ha-Kodoshim/Holy of Holies) on the north side, outside of the curtain that forms the external boundary of the Kodesh Ha-Kodoshim, and that the Menorah needs to be stationed on the south side of the Kodesh, similarly near the curtain behind which is the Kodesh Ha-Kodoshim. (Shemos 26:35) In Parshas Tetzaveh (ibid. 30:6), we are taught that the Mizbach Ha-Zahav (Golden Altar), which is the third of the Keilim stationed in the Kodesh, needs to likewise be in front of the curtain that bounds the Kodesh Ha-Kodoshim. (The Mizbach Ha-Zahav stood between the Shulchan and the Menorah, slightly to the east of them. V. Rashi on Shemos 26:35, from Chazal.)

Please click open this link for a diagram of this all.

The schematics impose upon us a few very serious questions: Why were the Shulchan, Menorah and Mizbach Ha-Zahav relatively close to the Kodesh Ha-Kodoshim rather than being close to the entrance of Kodesh, such that Kohanim who used these Keilim for Avodah (Mishkan Service) needed to walk across the Kodesh to access them? And why was the Mizbach Ha-Zahav in the middle, slightly closer to the entrance of the Kodesh? The Halacha is that the Kohen first starts to light the Menorah and only then burns Ketores (Incense) on the Mizbach Ha-Zahav; as such, one would expect the Menorah to be close to the entrance of the Kodesh, with the Mizbach Ha-Zahav further away. However, on the contrary, the Mizbach Ha-Zahav was the closet Keli to the entrance of the Kodesh, even though it was not utilized until later, after the Menorah.

Each of the Keilim in the Mishkan had great symbolism. The Shulchan, which held Lechem Ha-Panim (Showbread), represented Hashem’s providence, sustenance and control of the universe (v. Seforno on Shemos 25:23). The Menorah, according to the Netziv, represented wisdom, and Chazal state that the Western Lamp of the Menorah evidenced that the Shechinah (Divine Presence) resides among B’nei Yisroel. The Mizbach Ha-Zahav represented exalted Avodah of Hashem, for Ketores is the highest manifestation of korban (sacrificial) service.

This symbolism actually emboldens our questions above, as since the Mishkan's Keilim represented Hashem’s interaction with man and the universe, all the more so would one expect these Keilim to be closer to the entrance of the Kodesh, so that the Kohanim would be able to access and be inspired by them more readily. Why were these Keilim further from the entrance and hence closer to the Kodesh Ha-Kodoshim? In fact, the Torah specifically denotes these Keilim as relating to the Kodesh Ha-Kodoshim, for it describes their location as before the curtain of the Kodesh Ha-Kodoshim (Shemos 26:35 and 30:6). What is the message here?   

Ketores represents the mystery and inscrutable nature of Divine Authority. It is Ketores that served as the implement for Hashem's punishment of Korach and his followers, and that likewise and paradoxically served to stop the plague later in Parshas Korach. Ketores stands for apparent contradiction and enigma, reminding us that cannot truly understand Hashem or perceive Him with our limited senses. He and His mastery over the world are beyond our grasp. This is why Ketores is essentially an offering of smoke and scent, as they are intangible entities and are removed and unearthly, as opposed to korbonos of foodstuffs.

As such, a Kohen who enters the Kodesh first encounters the Mizbach Ha-Zahav, as it must be established from the outset that when drawing near to the locus of the Shechinah, one must drop all sense of human definitions, expectations and understanding. It is a realm that is simply beyond us. 

This is likewise the message of the Shulchan, Menorah and Mizbach Ha-Zahav being located close to the curtain that bounds the Kodesh Ha-Kodoshim, and it is the reason why the Torah associates these Keilim with the Kodesh Ha-Kodoshim, for as much as these Keilim symbolize concepts that are meaningful for human beings and reflect Hashem's involvement with the natural world - such as sustenance, protection, wisdom and so forth - it must be accepted from the start that we need to encounter and address these concepts with a mindset that we cannot really understand, for they emanate from Hashem, Who is beyond our grasp. It is only from the perspective of the Kodesh Ha-Kodoshim, which is basically off-limits to man and represents the sphere of Hashem, that His interactions and involvement with the universe can be fathomed. 

Taking this down to contemporary human reality, we are taught by the configuration of the Kodesh and its Keilim that we cannot expect to comprehend and that we certainly cannot demand an intellectually satisfying explanation of how the universe is run. We must submit to the fact that we are of limited cognizance, and that Hashem manages the universe with His own wisdom and methodology, which are totally beyond our grasp.

Our role is to humbly walk before Hashem, absent any sense of entitlement or demand to truly perceive His ways. Such a person encounters Hashem on His terms and merits to enter the Kodesh of his own life at all moments.